Molding process and mold holding frame therefor



June 20, 1961 c. J. DIDION 2,988,792

MOLDING PROCESS AND MOLD HOLDING FRAME THEREFOR Filed July 17, 1959 WM 44 l VA QTToPA EKS United States Patent 2,988,792 MOLDING PROCESS AND MOLD HOLDING FRAME THEREFOR Charles J. Didion, 6317 Monterey Drive, 1 St. Louis 23, Mo. Filed July 17, 1959, Ser. No. 827,866 7 Claims. (Cl. 22111) This invention relates to a mold holding frame and in. particular is concerned with such a frame that is adapted to be used with conventional snap, slip or popoif molding flasks and the like to obviate the necessity of using mold boards. I

In the use of sand molds in conventional foundry practice in the past, mold boards have been required to be used upon which the sand molds are placed. In the pouring of molten metal in the casting operation such boards have been subjected to intense heat and their life is extremely short. These boards, upon which the sand molds are placed and which are used in carrying molds from one spot to another, represent a substantial investment and it is a purpose of the instant invention to make their use unnecessary by the provision of a novel mold holding. frame of metal or the like which can be used over and over again.

Essentially this invention contemplates the employment of a mold holding frame having inclined inner surfaces. The holding frame is used at the beginning of the sand charging operation when sand is placed in the bottom half of the flask in conventional practice. The frame is adapted to wedge against and compact the sand in such a manner that when the flask is inverted and the flask ultimately removed from the mold, the frame forms a bottom base for the mold. The frame is equipped with hand holes so that the frame with the mold can be picked up and transferred from place to place.

By virtue of a latch and hinge arrangement the frame can be broken apart once the mold has been transferred to a convenient rest place, such as a concrete base or the like that can withstand the heat in the pouring operation and can readily be removed from the mold without breaking it apart or disturbing it in any manner.

The frame is very simple in construction and can be employed with any type of flask or similar type of mold container having inclined or perpendicular sides. The frame is extremely simple/to use and, as brought out above, it is adaptable for diiferenttypes of operations by virtue of its simplicity in design. As a consequence of the frame, a very substantial saving in cost of mold boards can be effected and the frame can be employed by unskilled workmen with no complicated instructions required.

Accordingly, it is a primary object of this invention to provide a molding process and a mold holding frame therefor in which a frame having inclined inner surfaces can be used to confine the sand within a flask and retain the sand in the molded form once the flask has been removed. 1

It is a further object of this invention to provide a molding process and a mold holding frame therefor in which the frame has inclined sides and is adapted to be used with molding flasks and the like to compact sand therein. After the flask has been removed the sand mold may be supported by the frame and moved from place to place with the frame being adapted to be broken apart therefrom or unhinged in a very simple and expeditious fashion.

Still another object of this invention is to provide a mold holding frame having inclined sides which are adapted to support the bottom of a sand mold and in which the frame is of generally rectangular configura- Patented June 20, 1961 tion with the provision of hinges and a latch so that the frame can be broken apart from the sand mold without disturbing it. The frame is further provided with a hand hole for convenient grasping of the frame in carrying the mold and the frame from place to place.

Yet a further object of this invention is to provide a mold holding frame and a process of molding which can be employed by unskilled workmen for various types of molding operations.

For the purpose of illustration of this invention, there is shown in the accompanying drawing a preferred embodiment thereof. It is to be understood that these drawings are for the purpose of example only and that the frame illustrated therein is not confined to use for the particular molding flask or pattern shown and can be employed in general usage.

In the drawings:

FIGURE 1 is a view in vertical section through an inverted bottom flask with a pattern and showing the frame placed on top of the bottom half of the sand mold;

FIGURE 2 is a view in vertical section showing the top and bottom flask with sand and pattern therein in the conventional upright position and further showing the holding frame at the bottom of the bottom flask;

FIGURE 3 is a view in vertical section taken similarly to FIGURE 2 but at a further stage in the mold preparing operation after the pattern has been removed;

FIGURE 4 is a view in vertical section taken through the mold and showing the holding frame at the bottom with the top and bottom flask having been removed;

FIGURE 5 is a view in front elevation of the sand mold with the holding frame;

FIGURE 6 is a top plan view of a sand mold with the mold holding frame shown after it has been unhinged and broken apart from the mold;

FIGURE 7 is an enlarged top plan view of the mold holding frame with a fragmentary sectional view of the hinge structure;

FIGURE 8 is a view in front elevation of the mold holding frame;

FIGURE 9 is a view in side elevation of the frame taken from the left-hand side of FIGURE 7 and showing the hinge structure;

FIGURE 10 is a view in side elevation taken from the right side of FIGURE 7 showing the latch construction;

FIGURE 11 is an enlarged fragmentary view in elevation showing the latch structure;

FIGURE 12 is an enlarged view in elevation on the line I212 of FIGURE 6 showing part of the latch structure;

FIGURE 13 is a view in section taken on the line 1313 of FIGURE 11 showing the details of the latch structure; and

FIGURE 14 is a view in section taken on the line 14-14 of FIGURE 11 showing further details of the latch structure.

The mold holding frame, generally indicated by the reference numeral 20, will first be described in detail as shown in FIGURES 7 through 14. As best shown in FIGURE 7, the frame is comprised of four members 22, 24, 26 and 28. A hinging mechanism, indicated by the reference number 30, connects the members 22 and 24 in hingeable relationship, while a latch mechanism 32 connects the members 26 and 28 when in the operated position to form a rigid frame structure.

Each of the frame members, as shown in FIGURES 7-10, is provided with a hand hole 34. This is provided by a recess extending from the side of the frame into the bottom so that the entire frame can be picked up from a flat base by any two of the sides by grasping the frame through the hand holes. It will also be noted that no protuberances are formed by this means.

The individual frame members are uniform in their general structure and a description of one will be understood to apply to them all. In the general structure of the frame members, such as frame member 22 shown in FIGURES 7 and 12, it will be noted that there is a flat base 36 with a sloping inside face 38 and a slightly angled outer face 40. The outer face 40 is of the same inclination as the flask with which the frame is to be used and for the purpose of illustration a taper of is shown as this is fairly conventional for flask structures. It is, however, to be understood that the slope of this face is variable depending upon the flask with which the frame is to be used. Likewise the slope of the interior face 38 is variable. It is, however, important that there be an inclination of the interior face in order that a wedging action may be imployed upon the sand when the frame is placed in the flask as will be further described hereinbelow.

The hinge 30, best shown in FIGURES 7 and 9, is of a conventional plate and pintle structure. The hinge is formed by two plates 42 and 44 connected to a pintle 46 as shown in the broken away view of FIGURE 7. The plates are set within slight recesses in the members 22 and 24 in order that a vertical axis for the pintle 46 may be obtained, it being understood that the surfaces of the recess in the frame members are vertical in order that this relationship may be effected. Also by this arrangement no protuberances beyond the outside face are formed. The hinge structure although of a preferred type is not critical however and other types of conventional hinging arrangement may be employed.

The latch 32 is best shown by reference to FIGURES 7 and through 14. As shown in FIGURE 12, the end of member 22 is squared away at the face 50 and provided with locking stud 52. The member 28 is provided with a sliding latch 53 supported within a recess 54 of the member 28. This is best shown in FIGURES l1, l3 and 14. The latch 53 slides by virtue of the slot 55 provided in it which receives guide studs 56 and 58 to maintain the proper guided relationship. A finger guide 59 is provided on the sliding latch in order that the latch may be moved back and forth in the operated and unoperated position. At the front end of the latch, or the left side as shown in FIGURE 11 a cutout keyway 60 is provided so that the latch may be locked upon the locking stud 52. This latch has been shown as a preferred embodiment for the purpose of illustration only and here again it is to be understood that the invention is not limited to the particular form of latch shown, but that other latches may likewise be employed.

It should be pointed out, however, in connection with both the hinge 30 and the latch 32 that it is desirable that these be set within the exterior surfaces 40 of the frame members in order that the entire frame may. be nested within a flask. Thus by this arrangement there are no protrusions beyond the exterior of the frame that would prevent its nesting.

Molding process and use of mold holding frame Reference will now be had to FIGURES 1 through 6 showing the molding process and the application of the mold holding frame. In this description it will be understood that the conventional molding operation in which sand molds are employed in the usual foundry practice is followed. Thus, flasks of various shapes and configurations are used and the holding frame can be formed to be used with the different types that are conventionally employed in this art.

In FIGURE 1 a flask 61 is shown that is a conventional bottom flask and which is filled with sand 62 over a pattern plate 64. For the purpose of simplicity the filling holes connected with the pattern plate have been depleted, it being understood that these are employed in the usual fashion. In the operation ofsthis invention it will be understood that the sand 62 is filled within the flask 61 andvoverthe pattern plate in the usual manner. Then the mold holding frame 20 is .placed within the top inner periphery of the flask in such a manner that it nests therein as shown in FIGURE 1. The holding frame is pressed down tightly so that the wedging action againstthe sand will be effected by virtue of the inclined inner face 38 of the frame.

After the operation has been effected as shown in FIG- URE l, the usual mold filling operations are carried out. Thus, as shown in FIGURE 2, the bottom flask 61 has been inverted and the top flask 66 has been placed thereover and filled with a sand layer 68. The top sand layer 68 is tamped down tightly in the usual manner as will be well understood in the art.

After the operation in FIGURE 2 has been carried out, the top flask 66 is drawn apart from the bottom flask and the pattern plate is removed as shown in FIGURE 3.

After the squaring of the flask, as shown in FIGURE 3, and the conventional operations connected therewith have been executed, the top and bottom flasks 66 and 61, respectively, are removed from the sand mold 70 formed by the joining of the layers 62 and 68. The mold openings 72 are formed therein. As shown in FIGURE 4 the sand mold 70 is securely supported at the bottom by the wedging action of the mold holding frame and the inclination of the inner faces 38. It will also be understood that the faces of the sand mold that are contiguous with the slanting faces 38 are compacted by virtue of this wedging action to provide additional strength at this point. FIGURE 5 is a view in elevation taken similarly to FIGURE 4 and from these drawings it will be readily understood that the entire unit comprising the mold 70 and the holding frame 20 can be transported by picking the same up by carrying the frame and grasping the same at the hand holes 34 to transport it from place to place.

The final operation in the formation of the sand mold is shown in FIGURE 6 where the latch 32 has been broken apart by moving the latch to the left from the position shown in FIGURE 1.1. This permits the sides 26 and 28 to be swung apart about the hinge 30 as shown in FIGURE 6. The remaining mold 70 leaving downwardly tapering bottom sides as shown in the dotted lines to conform with the configuration of the frame can be supported upon a concrete base or the like and filled with molten metal in the usual pouring operation.

It will be understood that the mold holding frame may be made of aluminum for light weight or other conventional materials of construction since the frame does not have to withstand heat as it is removed from the mold before the pouring operation. The frame may also be made extensible through telescope structure so that it can be adapted to fit diiferent sizes of flasks or be taken off finished mold by telescoping other of its sides. By virtue of the process described and the particular mold holding frame disclosed herein, there has been provided a very simple and expeditious device for handling molds which completely obviates the necessity of using mold boards or the like. The mold holding frame is very simple in construction and can be used by relatively unskilled workmen and represents a substantial saving in molding operations and the cost of mold handling paraphernalia.

Various changes and modifications may be made within this invention, such as altering the slope and inclination of the sides of the frame members. Further, it should be understood that in the rare instances where flasks other than rectangular are employed, the frame may be made to conform to the same configuration in obvious fashion, whether this shape be cylindrical, triangular or otherwise. Likewise, modifications and alterations may be made within the hinge and latching mechanism as previously pointed out. Such changes and alterations are within the skill of the art and fall within the scope and teaching of this invention as defined by theclaims appended hereto.

What is claimed is:

1. In a process for preparing foundry molds, the improvement comprising taking an inverted mold flask filled with sand and inserting a frame having an open center and a wedge-shaped cross-section around the inner periphery of said flask in nested relation, applying pressure upon said frame to compact the sand and form an area of greater compaction in the region contacted by said frame in order that the sand mold may be held together thereby, said pressure applying step being carried out to the extent that the sand is pressed out at least flush with the frame, inverting the flask, subsequently removing said flask from the frame and the sand mold to leave a composite unit, placing said frame and mold unit upon a flat base with the frame supporting the bottom of the mold and breaking apart said frame from the mold by unfastening a corner of the frame and opening the frame about an oppositely hinged frame corner to leave the mold supported solely by said base.

2. A sand mold holding frame for use inside molding flasks, said frame being comprised of four metal frame members defining a rectangular shape having an open center, said frame having a hinge at one corner and having a latch at an opposite corner and said frame members each having an inner surface inclining downwardly toward said open center and an outer surface nesting against the inside walls of the flask.

3. A sand mold holding frame for use inside molding flasks, said frame being comprised of four metal frame members defining a rectangular shape having an open center, said frame having a hinge at one corner and having a latch at an opposite corner and said frame members each having a generally triangular cross-section comprising a flat base, an inner surface inclining downwardly toward said open center and forming an acute angle with said base and an outer surface nesting against the inside walls of the flask.

4. A sand mold holding frame for use inside molding flasks, said frame being comprised of four metal frame members defining a rectangular shape having an open center, said frame having a hinge at one corner and having a latch at an opposite corner and said frame members each having an inner surface inclining downwardly toward said open center and an outer surface nesting against the inside walls of the flask, and handle means on said frame whereby the frame may be picked up from the outside thereof while resting on a flat base.

5. A sand mold holding frame for use inside molding flasks, said frame being comprised of four metal frame members defining a rectangular shape having an open center, said frame having a hinge at one corner and having a latch at an opposite corner and said frame members each having a generally triangular cross-section comprising a flat base, an inner surface inclining downwardly toward said open center and forming an acute angle with said base and an outer surface nesting against the inside walls of the flask and handle means on said frame comprising recesses forrned within the outside surfaces of oppositely disposed frame members whereby the frame may be smoothly nested within a flask and may be picked up from the outside while resting on a flat base.

6. A sand mold holding frame for use inside molding flasks, said frame being comprised of four metal frame members defining a rectagnular shape having an open center, said frame having a hinge at one corner and having a latch at an opposite corner and said frame members each having a generally triangular cross-section comprising a flat base, an inner surface inclining downwardly toward said open center and forming an acute angle with said base and an outer surface having an inclination generally parallel to and resting against the inside wall of the foundry flask with which the frame is employed.

7. A sand mold holding frame for use inside molding flasks, said frame being comprised of four metal frame members defining a rectangular shape having an open center, said frame having a hinge at one corner and having a latch at an opposite corner and said frame members each having a generally triangular cross-section comprising a flat base and an inner surface inclining downwardly toward said open center and forming an acute angle with said base and an outer surface having an inclination generally parallel to and nesting against the inside wall of the foundry flask with which the frame is employed, said hinge and latch being recessed within the outside surfaces of said frame members whereby the frame may be smoothly nested within the flask, said hinge having a vertical pivot axis and said latch comprising a stud at the end of one frame member and a sliding catch engageable therewith supported upon an adjacent end of an adjacent frame member.

References Cited in the file of this patent UNITED STATES PATENTS 1,746,146 Diehl Feb. 4, 1930 2,144,859 Spensley Jan. 24, 1939 2,799,064 Schucker et al July 16, 1957 2,841,841 Hines July 8, 1958 FOREIGN PATENTS 120,040 Switzerland May 2, 1927 OTHER REFERENCES Foundry Work, W. C. Stimpson et 8.1., page 8, 1943. 

